1. Field of the Invention
This invention relates to a liquid crystal display apparatus and an electronic apparatus wherein, for example, both of reflective type display and transmissive type display are used.
2. Description of the Related Art
A liquid crystal display apparatus is used as a display apparatus for various electronic apparatus making the most of the characteristics of a small thickness and lower power consumption. In particular, a liquid crystal display apparatus is used, for example, as a display apparatus of a notebook type personal computer or a car navigation system or employed in various other electronic apparatus such as a portable digital assistant (PDA), a portable telephone set, a digital camera or a video camera.
Liquid crystal apparatus are roughly divided into two types including a transmissive type and a reflective type. In a liquid crystal display apparatus of the transmissive type, light from an internal light source called backlight is controlled between transmission and interception by a liquid crystal panel to display an image. On the other hand, in a liquid crystal display apparatus of the reflective type, external light such as sunlight is reflected by a reflecting plate or the like and the reflected light is controlled between transmission and interception by a liquid crystal panel to display an image.
In a transmissive type liquid crystal display apparatus, the backlight consumes power by more than 50% the total power consumption of the apparatus, and it is difficult to reduce the power consumption. The transmissive type liquid crystal display apparatus has a problem also in that, where the surroundings are light, the display looks dark and therefore the visibility is low.
On the other hand, in a reflective type liquid crystal display apparatus, since it does not include a backlight, it does not have the problem of high power consumption. However, it has another problem in that, where the surroundings are dark, the visibility is very low.
In order to eliminate the problems of both of transmissive and reflective type display apparatus, a liquid crystal display apparatus of the reflective and transmissive type which implements both of transmissive type display and reflective type display using a single liquid crystal panel has been proposed. The reflective and transmissive type liquid crystal display apparatus makes use of reflection of ambient light for display when the surroundings are light, but makes use of light of a backlight for display when the surroundings are dark.
Incidentally, various liquid crystal display apparatus which make use of IPS (In Plain Switching) or FFS (Fringe Field Switching) have been proposed in order to assure a wide angular field of view. Such liquid crystal display apparatus are disclosed, for example, in Japanese Patent Laid-open Nos. 2002-229032 (hereinafter referred to as Patent Document 1), 2001-42366 (hereinafter referred to as Patent Document 2), 2005-338256 (hereinafter referred to as Patent Document 3), 2005-338264 (hereinafter referred to as Patent Document 4), 2006-71977 (hereinafter referred to as Patent Document 5) and 2005-524115 (hereinafter referred to as Patent Document 6).